Method of welding composite articles



March 8, 1932. w. A. WISSLER METHOD OF WELDING COMPOSITE ARTICLES Filed July 7, 1928 INVENTOR. 214%,, a. WM

. ATTORNEYS.

Patented Mar. 8, 1932 UNITED. STATES WILLIAM A. WISSLER, OF JACKSON HEIGHTS, NEW YORK, ASSIG-NOR LITE COMPANY, A CORPORATION OF INDIANA PATENT oFFIca 'ro mums swani i METHOD OF WELDING COMPOSITE ARTICLES i i Application filed July 7, 1928. Serial No. 291,006.

. My invention relates to methods of making composite articles consisting of a foundation metal and a shield or surface layer of metal deposited on the foundation in a fused condition.

Machine tools, for example, are made in this way by depositing high speed steelor stellite on the tip or cutting portion of a steel shank by means of an oxy-acetylene torch or an electric are. A deposit of metal of suflicient thickness is usually formed to permit regrinding and sharpening of the tool. Sometimes a notch or a depression is formed in which metal is deposited. Other articles such as railway rail members are shielded or armored by depositing stellite on the parts that are subjected to wear. In forming the deposit the foundation metal becomes highly heated to a considerable depth, often to a red heat, and as a result the fused metal cools and solidifies slowly in its interior and in portions which are in contact with the foundation metal. The result is that the portion of the deposited metal exposed to the air is the first to solidify. When the fused metal is completely solidified, a shrinkage pocket or porous spot occurs in the portion in which solidification is delayed.

It is among the objects of my invention to provide methods and means of depositing such fused-on shields without producing an unsound portion within the body of the deposited metal.

I have found that if the foundation metal is cooled so that the solidification of the fusedon metal will occur progressively from the surface of the foundation metal toward the surface of the fused-on metal, the porous portion will either not be formed or will be so close to the surface that a light grinding will remove it. One method of cooling the foundation metal consists in partially submerging the metal in a cooling bath of water or other liquid, in such a manner that the portion upon 3 which the fusion heat is directed will project above the surface of the bath. Such an arrangement will effect the desired cooling of the foundation metal and prevent the formation of a pipe in the fused-on metal.

A more practical device which I have used is shown in a side elevational View in Fig. 1 and in Fig. 2 in a view in cross-section taken along the line 11-11 of Fig. 1. Cooling mem here are held by any convenient means, such as the clamps 2 in contact with the foundation metal 3. The cooling members 1 are provided with guards of heat insulating material 4 which may be strips of asbestos. These members protect the members 1 from the intense heat used to fuse the shielding metal.

The members 1 may be solid bloclm of metal, for example, copper, but I prefer to provide channels 5 through which a cooling fluid may be supplied at the desired rate from a suitable source through the pipes 6 and discharged 35 through the pipes 7. For the best results the cooling members 1 are preferably shaped to conform to the surface of the foundation member. The surface upon which the metal is deposited is generally located a. short dis- 7n tance above the surface of the cooling members. This distance may be regulated according to the rate at which heat is supplied to the metal and the rapidity with which the cooling members conduct away the heat. 7 Heat should not be extracted from the foundation metal rapidly enough to prevent the deposited metal from forming a strong bond with the foundation metal, but there should be enough cooling to cause a progressive solid 30 ification from the surface of the foundation metal as the fused metal is deposited and to prevent an accumulation of fused metal in the interior of the deposit 8. The cooling may also be regulated by increasing or decreasing the flow of cooling fluid through the channels 5.

I claim as my invention:

Process of building up a composite metal article consisting of a body of foundation so metal and a surface layer of metal more Wearresistant than said foundation metal, which comprises contacting the said body with coo1- ing members in such manner that a ortion of the body protrudes a regulatable istance I beyond said cooling members and depositing on said protruding portion a layer of the surfacing metal by means of a gas Welding flame, the extent of protrusion of said portion being 10 so regulated as to produce progressive solidification of the deposited metal from the surface of said body.

In testimony whereof, I afiix my signature.

WILLIAM A. WISSLER. 

